Authors van Dongen J, Tekle FB, van Roijen JH
Review Date Feb 2012
Citation BJU International 2012 Jan 5. doi: 10.1111/j.1464-410X.2011.10781.x
Microsurgical vasectomy reversal is an effective and cost-effective method of reinstating fertility in a man who has previously had a vasectomy. The current literature indicates that the success rate (i.e. patency and pregnancy rates) is dependent primarily on the time elapsed since vasectomy and the age of the female partner. Postoperative semen parameters have not been shown to be important prognostic factors for pregnancy.
To determine the influence of smoking, postoperative semen characteristics and the use of assisted reproductive technologies (ART) on pregnancy rate in a contemporary series of men undergoing vasectomy reversal in a single hospital in the Netherlands.
Between January 2002 and January 2009, 186 vasectomy reversals were performed. Of the 171 patients who could be contacted for follow-up, 162 attempted pregnancy and constitute the study group.
Semen analysis was performed 3 months after the procedure and at subsequent 3-monthly intervals. Patient characteristics and surgical information were obtained from a computerised database, and follow-up data were collected by telephone interview.
A multivariate Cox regression model was used to discern possible prognosticators with respect to pregnancy outcome.
The overall patency rate (presence of any sperm with tails, with or without motility) was 91.4%. The natural pregnancy rate was 44.4% and a subsequent 14.2% of patients conceived using ART, resulting in a total pregnancy rate of 58.6%.More than one pregnancy was obtained by 20.4% of couples.
Smoking of the male or female partner did not influence the probability of conception.
In a multivariate model that included, among other factors, time since vasectomy, female age and semen characteristics, only sperm motility was significantly related to natural pregnancy outcome. The probability of obtaining a natural pregnancy within 2 years after surgery is 53% for men with sperm motility >20% (WHO a+b) compared to 19% for men with sperm motility <5% (P= 0.003).
A clear and significant association between sperm motility and the probability of conception was found, whereas smoking, female age and time since vasectomy appeared to have no influence on pregnancy outcome in this patient cohort.
The use of ART accounted for an absolute increase in pregnancy rate of 14.2%.
Points to Note
- This was a relatively small series of patients undergoing vasectomy reversal but appeared to have complete follow-up data on a high proportion of patients. For 16 men it was the second reversal operation.
- The lack of association with time since vasectomy, a factor widely considered to be important in the success of vasectomy reversal, has been shown in another recent study and was attributed to good modern surgical techniques. The mean time since vasectomy in this study was 7.9 years which may not have been long enough to see the effect of this variable.
- The authors report that smoking was not associated with pregnancy rate after vasectomy. However, it should be noted that smoking was defined as ‘any smoking’, a not very accurate measure. Also the study did report a higher proportion of motile sperm in non-smokers (29.5%) than smokers (23.4%) but the p-value of 0.06 caused the authors to dismiss this potential association.
- ART was used by 30% of couples for whom natural pregnancy did not occur within some period after vasectomy reversal (this clinic advises waiting 1-2 years) with less than half achieving a pregnancy.
- The main novel finding of the study was that sperm motility was strongly associated with pregnancy rate although other sperm parameters were not. This finding needs to be replicated in other studies.